The present invention relates to a construction technology of an airbag cover mounted on a passenger airbag of a vehicle.
For example, an example of a conventional passenger airbag apparatus is disclosed in the following patent document 1 (Japanese Unexamined Patent Application Publication No. 2004-338633)
In the passenger airbag apparatus, a tear line for use in rupturing an airbag cover is provided in an airbag cover for covering a passenger airbag. The airbag cover is ruptured along the tear line when the vehicle is in collision and a developing door is developed, and the airbag cover allows the passenger airbag to be developed and expanded outside the airbag cover. Further, in the passenger airbag apparatus, a housing case for housing the passenger airbag is jointed on a rear surface of an airbag-cover body portion by means of a vibration welding operation.
Incidentally, in designing this kind of airbag apparatus, it is required that the housing case for housing the passenger airbag is assuredly jointed to the airbag cover side by means of the vibration welding operation. Specifically, in a case that the airbag-cover body portion is formed into a curved shape in designing or the like, the curved shape disturbs a vibrating motion of the vibration welding operation, and there is a high demand for uniformly jointing a portion where the body of the airbag cover and the housing case face each other by devising a structure regarding the vibration welding operation.
Accordingly, the present invention is made in consideration of the above-described view point, and in the airbag cover for covering the passenger airbag of the vehicle, the invention provides a technology effective for assuredly jointing the housing case side for housing the passenger airbag and the airbag-cover body portion side by means of the vibration welding operation.
Further objects and advantages of the invention will be apparent from the following description of the invention.